Solar Energy, Materials Solutions for Cells and Modules

Electrical contacts represent a critical element of photovoltaic technology and are problematic for silicon solar cell production. Current processes that use silver and nickel/copper top contacts are not cost effective: silver is too expensive and the use of a nickel diffusion barrier adds cost and complexity to the assembly process. Alternative metals such as aluminum and copper have thus far been unsuccessful because of their inherent chemistries. This project will develop metallic-nanoparticle-based conductive inks that can be applied through non-contact print techniques. Phase I demonstrated that a new aluminum ink that could be deposited and cured in ambient conditions. This ink provided a cured resistivity 2.3 times that of bulk aluminum. The aluminum ink provided Ohmic contacts and an enhanced BSF (back surface field) layer on silicon. Phase II will optimize the aluminum inks, refine the deposition process, and generate high efficiency solar cell prototypes. Commercial Applications and other Benefits as described by the awardee: The technology should provide an accurate, robust, reliable, and cost-effective method for increasing electrical energy efficiency in silicon solar cell production and usage. The technology would simplify the manufacturing process for solar cells and lower costs, thereby accelerating the commercialization of photovoltaic technology.